NEW YORK, Aug 3 (Reuters) - Currency market fluctuations in the first quarter of 2018 had the smallest negative impact on North American companies’ financial results since 2011, according to data from currency risk consulting firm FiREapps on Friday.

For the first quarter of this year, the negative impact of currency movements on those companies, including from the United States, Canada and Mexico, that quantified an exchange rate effect was $37 million. That was the smallest for any quarter since a $20 million impact in the first quarter of 2011, when FiREapps began collecting the data.

The first-quarter 2018 impact was also about $1 billion below what it was in the fourth quarter of 2017.

The number of North American companies reporting negative currency impacts, including those that did not quantify the loss but reported an impact, also was the lowest in years, the report showed.

While the dollar fell against a basket of currencies in the first quarter, it gained sharply in the second quarter and companies reporting results for the June quarter in recent weeks have begun to cite it as a negative influence.

The dollar index is up about 3 percent for the year so far.

The foreign currency earnings of U.S. multinational companies are worth less in dollars when the dollar is stronger. A firmer U.S. currency also makes American-made goods and services more expensive overseas. (Reporting by Caroline Valetkevitch; editing by Jonathan Oatis)